Fort Worth daily gazette. (Fort Worth, Tex.) 1882-1891, 1887-01-28
PRECIOUS METALS.
How Gold and Silver Are Refined at the
Assay Office.

Assay Office.
New York Post.
In the very heart of Wall street are the
United States Sub-Treasury and the Assay
| Office. Here is the true heart of the tinan-
cial world; If it is irregular in it's beating
notice how quickly the speculative pulse
is affected. The Sub-Treasury deals with
money after it is coined, but the Assay
Office takes the virgin gold and silver, or
these metals when they are debased, and
determines their value, using the govern
ment standard of coinsge as basis.
The office is intended to accommodate
the bullion interests of New York, ard it
is used by brokers, bankers, merchants
and jewellers. Any one having god or
silver which, when assayed, will amount
to 500 or over, may deposit it. He will
receive its value in coin or in fine gold,
or, if it is silver, in tine silver bars. The
gold and silver bars have their weight
stamped upon them, and the former bear,
under the government seal, the value in
gold coin as well. The use of these bars
has saved the Government heavy ex-
pense, as they have been largely en-
plOyed in the arts and manufactures, thus
preventing the melting down of gold. To
determine just how an exchange shall be
made, chip is taken from the metal
brought to be assayed, and it is melted
by itself and poured into molds. These
small samples are assayed, and by calcu-
lation the proportion of pure metal is in
Dictated. OF course deductions must be
made tor the cost of parting, refining,
ETC., but the net result is paid to the de-
positor.
To obtain the best results in the sepa-
rating department the deposits are 81
combined that the gold granulations shall
have over two parts of silver to one of
gold, care being taken that any copper
that may be present shall not exceed per
cent. of the mixture. About tWenty-f five
thousand ounces can be treated in four
kettles. The acid is added to the granu-
lations in successive portions from
reservoir on floor above, into which it is
forced by air pressure from revolving
cylinder in the basement. 1t is boiled
about five hours, then allowed to cool,
and afterWard siphoned into silver re-
duCing tanks, four in number. The re-
moval of the silver in the acid solution
leaves the gold in the dissolving kettle;
to this fresh acid is added, and 1t is re-
moved to another kettle, acid being again
added twice. The resulting. weak solu-
tions of silver are siphoned off, and after
the third repetition of this process gold
results, which, when melted, fluxed and
cast into bars, is $4,000 to 996 1000
fine.
The solution of silver which is obtained
by the above process is, after settling
process, boiled by the application of
steam ABOUT five hours in lead vats. In
these copper plates are plunged, a por-
ton of the copper gradually replacing the
silver in the solution. The copper solu-
ton is then siphened into concentrating
tanks, and the silver, after being scraped
from the copper plates, is placed in a
filter, where it is washed, AID, when
melted, is found to be from 999 to 1894
thousandths fine.
The men, who are busily engaged eight
hours day in pouring molten gold from
crucloIes Into molos, are as careless in
their actions as if they were handling
iron. II 1t were possible for any class of
men to grow tired of the glimmer aad
CLINT OF gold, these men must be the for
tuHate individuals. Some one undoubt-
edly keeps close watch on
them, out it is not apparent,
and they do not seem to De re-
stricted in their freedom because thew
work in the precious metal. When they
have finished work they change their |
clothing and go home. There has been
but one arrest among them in years. A |
few dollars worth of gold was found in |
the pocket of workman, but the grand |
jury did not find against him, the infer
ence being that some enemy had placed |
It there.